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v3.23.1

Financial Instruments - Fair value hierarchy (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Financial Instruments Measurements |  |  |
Transfers between fair value measurement levels | $ 0 | $ 0 |
Minimum | Reverse repurchase agreements | Government Securities and Obligations |  |  |
Financial Instruments Measurements |  |  |
Percentage of investment amount to collateralized deposits value | 102.00% |  |
Recurring |  |  |
Assets: |  |  |
Total | $ 88,715 |  | $ 207,856
Recurring | Level 1 |  |  |
Assets: |  |  |
Total | 13,640 |  | 7,924
Recurring | Level 2 |  |  |
Assets: |  |  |
Total | 75,075 |  | 199,932
Recurring | Money market funds |  |  |
Assets: |  |  |
Cash and cash equivalents: | 1,715 |  | 1,944
Recurring | Money market funds | Level 1 |  |  |
Assets: |  |  |
Cash and cash equivalents: | 1,715 |  | 1,944
Recurring | Corporate debt securities |  |  |
Assets: |  |  |
Short term investments | 6,075 |  | 16,445
Recurring | Corporate debt securities | Level 2 |  |  |
Assets: |  |  |
Short term investments | 6,075 |  | 16,445
Recurring | Yankee securities |  |  |
Assets: |  |  |
Short term investments |  |  | 1,999
Recurring | Yankee securities | Level 2 |  |  |
Assets: |  |  |
Short term investments |  |  | 1,999
Recurring | Bonds |  |  |
Assets: |  |  |
Short term investments |  |  | 2,988
Recurring | Bonds | Level 2 |  |  |
Assets: |  |  |
Short term investments |  |  | 2,988
Recurring | Treasury bills |  |  |
Assets: |  |  |
Cash and cash equivalents: | 6,973 |  |
Short term investments | 4,952 |  | 5,980
Recurring | Treasury bills | Level 1 |  |  |
Assets: |  |  |
Cash and cash equivalents: | 6,973 |  |
Short term investments | 4,952 |  | 5,980
Recurring | Reverse repurchase agreements |  |  |
Assets: |  |  |
Cash and cash equivalents: | 69,000 |  |
Short term investments |  |  | 178,500
Recurring | Reverse repurchase agreements | Level 2 |  |  |
Assets: |  |  |
Cash and cash equivalents: | $ 69,000 |  |
Short term investments |  |  | $ 178,500

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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